265/65R18 vs 275/65R18
275/65R18 is 0.5 inches taller and 0.4 inches wider. When your speedometer says 60 mph, you'd really be doing 61.0.
I have 265/65R18
I'm looking at 275/65R18
Close match
0.5 in taller. At 60 mph on the speedometer you'd really be doing 61.0.
- Within the 3% height difference most tire shops consider safe.
265/65R18 now 275/65R18 newTo scale
At an indicated 60 mph you're really doing 61.0 mph
+0.51″
Height
+0.39″
Width
+0.26″
Sidewall
All measurements
| 265/65R18 | 275/65R18 | Change | |
|---|---|---|---|
| Overall height | 31.56″ | 32.07″ | +0.51″ |
| Section width | 10.43″ | 10.83″ | +0.39″ |
| Sidewall height | 6.78″ | 7.04″ | +0.26″ |
| Wheel size | 18″ | 18″ | same |
| Distance per turn | 99.16″ | 100.77″ | +1.61″ |
| Turns per mile | 639 | 629 | −10 |
Speedometer after switching
Your speedometer is calibrated for 265/65R18. On 275/65R18:
| Speedometer says | You're really doing |
|---|---|
| 25 mph | 25.4 mph |
| 35 mph | 35.6 mph |
| 45 mph | 45.7 mph |
| 55 mph | 55.9 mph |
| 65 mph | 66.1 mph |
| 75 mph | 76.2 mph |
What changes on the vehicle
- Ride height goes up about 0.26″ (half the height difference).
- The tire turns 10 fewer times per mile, so your odometer will read low by about 1.6%.
- The sidewall is 0.26″ taller, on the same wheels.